Short- and medium-term prognosis of HIV-infected patients receiving intensive care: a Brazilian multicentre prospective cohort study.

OBJECTIVES: The characteristics of critically ill HIV-positive patients and the causes of their admission to intensive care units (ICUs) are only known through retrospective and unicentric studies. This study aims to fill this knowledge gap. METHODS: This is a prospective, multicentre cohort study of short- and medium-term prognostic factors. The setting consisted of ICUs of three tertiary referral hospitals from the three largest metropolitan areas in Brazil in the period January 2014 to November 2015. In all, 161 HIV patients over 18 years old were included. RESULTS: The clinical data of the outcomes (ICU mortality, hospital mortality and 90-day survival) were extracted from medical records using the REDCap®ï¸ web-based form and analysed with the MedCalc®ï¸ application. Median age was 41.7 [interquartile range (IQR): 34-50] years, the Simplified Acute Physiologic Score 3 (SAPS 3) was 64 (IQR: 56-74), and the Sequential Organ Failure Assessment Score (SOFA) was 6 (IQR: 4-9) points. The main causes of admission were sepsis (54.5%) and acute respiratory failure (13.7%). ICU and hospital mortality rates were 32.3% and 40.4%, respectively. In a multivariate analysis, time until ICU admission ≥ 3 days (P = 0.0013), performance status (Eastern Cooperative Oncology Group score, P = 0.0344), coma (Glasgow Coma Scale ≤ 8 points, P = 0.0213) and sepsis (P = 0.0003) were associated with increased hospital mortality. Coma (P = 0.0002) and sepsis (P = 0.0008) were independently associated with 90-day survival. CONCLUSIONS: Delayed ICU admission and the severity of critical illness determine the short- and medium-term mortality rates of HIV-infected patients admitted to the ICU, rather than factors associated with HIV infection. These results suggest that prognostic factors of HIV-infected patients in the ICU are similar to those of non-HIV-infected populations.

Fibroblast growth factor receptor 2 expression in apical periodontitis in mice.

AIM: To investigate the presence, localization and the possible correlation of the fibroblast growth factor receptor-2 (FGFR2) with inflammatory resorption of cementum, periodontal ligament and alveolar bone during development of apical periodontitis in mice. METHODOLOGY: Apical periodontitis was experimentally induced in mandibular first molars of mice by pulp exposure to the oral environment. Healthy teeth without pulp exposure were used as controls. At 7, 21 and 42 days following pulp exposure, the animals were euthanized and the jaws were prepared for analysis under conventional and fluorescence microscopy, immunohistochemistry (FGFR2), RT-PCR (RNAm levels of RANK, RANKL, OPG, Runx2 and cathepsin K) and enzyme histochemistry (cementoclasts and osteoclasts). Statistical analysis was performed by Kruskal-Wallis tests and Dunn's post hoc tests for multiple comparisons (α = 0.05) using SAS 9.4 software. RESULTS: FGFR2-positive cells were not observed in the tissues surrounding healthy teeth but were observed in teeth with periapical lesions from seven days after root canal contamination. At days 21 and 42 after endodontic infection, the increase in periapical lesion size was accompanied by significantly enhanced expression of FGFR2 (P < 0.0001), significantly increased intensity of inflammatory cells, number of osteoclasts (P < 0.0001) and cementoclasts (P < 0.0001), and significantly enhanced RNAm levels of RANK/RANKL/OPG, Runx2 and cathepsin K compared to day 0 (P < 0.0001). At 21 and 42 days, FGFR2 was also expressed on osteoblasts, fibroblasts and inside enlarged lacunae of cementocytes along with acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). At all periods and cells, FGFR2 expression was observed in the cell membrane and cytoplasm, but not in the nucleus. CONCLUSION: In mice, FGFR2 was not expressed in tissues surrounding healthy teeth but was expressed in apical periodontitis, specifically in the membrane and cytoplasm of osteoblasts, fibroblasts, lacunae of cementocytes, and acute and chronic inflammatory cells (macrophages, plasma cells and neutrophils). Its expression was correlated with the size of the periapical lesions.

The role of interleukins in vitiligo: a systematic review.

Vitiligo is a disorder of the skin that causes depigmentation and asymptomatic macules whose exact cause is still unclear. Although its aetiology is not fully elucidated, the main theory of its pathomechanism is that it is associated with the autoimmune process. There is few summarized information about the role of inflammatory mediators, as interleukins, in vitiligo, so our aim was to present a systematic review of the role of interleukins in vitiligo, focusing on interleukins. In this review, we included all studies assessing interleukin levels in vitiligo patients conducted up to June 2017. Quality assessment of these studies was performed using the Newcastle-Ottawa Scale (NOS). The interleukins mainly involved were IL-2, IL-4, IL-6, IL-10 and IL-17. The studies highlight the crucial role of IL-17 in the onset and progression of the disease, and its synergistic action with IL-2, IL-6 and IL-33. Dysregulated levels of the interleukins were also correlated with the stage of disease, the affected skin surface area, and indicated as the main factor for lymphocyte infiltration found in depigmented regions. These findings illustrate the growing need for new therapies targeting vitiligo and further research into the role of interleukins as an area of particular interest.

Nonadiabatic dynamics with intersystem crossings: A time-dependent density functional theory implementation.

In this work, we derive a method to perform trajectory-based nonadiabatic dynamics that is able to describe both nonadiabatic transitions and intersystem crossing events (transitions between states of different spin-multiplicity) at the same level of theory, namely, time-dependent density functional theory (TDDFT). To this end, we combined our previously developed TDDFT-based trajectory surface hopping scheme with an accurate and efficient algorithm for the calculation of the spin-orbit coupling (SOC) matrix elements. More specifically, we designed two algorithms for the calculation of intersystem crossing transitions, one based on an extended Tully's surface hopping scheme including SOC and the second based on a Landau-Zener approximation applied to the spin sector of the electronic Hilbert space. This development allows for the design of an efficient on-the-fly nonadiabatic approach that can handle, on an equal footing, nonadiabatic and intersystem crossing transitions. The method is applied to the study of the photophysics of sulfur dioxide (SO2) in gas and liquid phases.

Superoxide radical-generating compounds activate a predicted promoter site for paraquat-inducible genes of the Chromobacterium violaceum bacterium in a dose-dependent manner.

The purpose of the present study was to functionally evaluate the influence of superoxide radical-generating compounds on the heterologous induction of a predicted promoter region of open reading frames for paraquat-inducible genes (pqi genes) revealed during genome annotation analyses of the Chromobacterium violaceum bacterium. A 388-bp fragment corresponding to a pqi gene promoter of C. violaceum was amplified using specific primers and cloned into a conjugative vector containing the Escherichia coli lacZ gene without a promoter. Assessments of the expression of the ß-galactosidase enzyme were performed in the presence of menadione (MEN) and phenazine methosulfate (PMS) compounds at different final concentrations to evaluate the heterologous activation of the predicted promoter region of interest in C. violaceum induced by these substrates. Under these experimental conditions, the MEN reagent promoted highly significant increases in the expression of the ß-galactosidase enzyme modulated by activating the promoter region of the pqi genes at all concentrations tested. On the other hand, significantly higher levels in the expression of the ß-galactosidase enzyme were detected exclusively in the presence of the PMS reagent at a final concentration of 50 µg/mL. The findings described in the present study demonstrate that superoxide radical-generating compounds can activate a predicted promoter DNA motif for pqi genes of the C. violaceum bacterium in a dose-dependent manner.

Humoral immune transcriptome signature in myelomeningocele patients.

INTRODUCTION: Myelomeningocele (MMC) results from incomplete closure of the neural tube, and has a complex multifactorial etiology, including an inflammatory microenvironment. OBJECTIVE: We evaluated the contribution of humoral immune response for development of inflammatory milieu. METHODS: Using public repository Gene Expression Omnibus (GEO), we retrieve dataset transcriptome from the amniotic fluid of ten fetuses with myelomeningocele and ten healthy control fetuses to found differential gene expression associated with disturbances and inflammatory signatures in MMC. The identified DEGs were submitted to enrichment, network, and matrix correlation analyses. RESULTS: Our initial analysis revealed 90 DEGs in MMC, mainly associated with signaling pathways of inflammation, including the immune modules, humoral immune response and IFN-type I signatures. Protein-protein analysis (PPI) revealed an association with three protein networks; positive regulation of B cell proliferation constituted the largest network. Matrix correlation analyses showed that MMC alters the co-expression of genes related to inflammatory processes that promote microenvironment inflammation. CONCLUSION: These results revealed an altered humoral immune response in MMC patients, contributing to an inflammatory profile and providing opportunities for identifying potential biomarkers in myelomeningocele disease.

Analysis of the stomatognathic system functions and mastication muscles in children affected by molar hypomineralization (MH): a cross-sectional study.

PURPOSE: To analyze the functions of the stomatognathic system in children with or without molar-incisor hypomineralization (MIH). METHODS: For this cross-sectional study, 72 children aged 6-12 years were recruited and divided in two groups: with MIH (G1) and without MIH (G2). T-SCAN was used to verify the distribution of occlusal contacts, gnathodynamometer to measure maximum molar bite force, and Iowa Oral Pressure Instrument (IOPI) to assess the strength of facial expression muscles. The t test and paired t test (p ≤ 0.05) were used for statistical comparisons. RESULTS: The molars affected by MIH exhibited lower distribution of occlusal forces (p < 0.001) and lower maximum molar bite force (p < 0.05) compared to the molars in the control group. However, there was no difference between the MIH-affected sides compared to the unaffected side, nor between the molars affected by MIH and their antagonists (p > 0.05). There were no differences in the forces of the facial expression muscles between the groups. CONCLUSIONS: These findings suggest that MIH significantly impacts occlusal force distribution and bite force, but not facial expression musculature.

Epithelial-mesenchymal transition-like events in vulvar cancer and its relation with HPV.

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) still remains an obscure event in vulvar squamous cell carcinoma (VSCC). METHODS: Immunohistochemistry (IHC) expression of E-cadherin, ß-catenin, Snail, Slug, Twist and Vimentin was analysed in 87 VSCC, controlled for human papillomavirus (HPV) positivity, considering tumour front and central tumour as different morphological categories from the same tumour. RESULTS: Lower ß-catenin and higher Vimentin expression was associated with invasive front when compared with the central tumour (P=0.013 and P≤0.001, respectively). Higher expression of E-cadherin in central tumour was significantly related to absence of vascular and perineural invasion, lower invasion depth and ≥2 lymph node involvement. Loss of ß-catenin and high Slug, Snail and Twist expression was associated with HPV-negative tumours. Moreover, ß-catenin lower expression associated with gain in Slug expression predicts a subgroup with worst outcome (P=0.001). Lower expression of ß-catenin in both central tumour and invasive front correlated with lower overall survival (P=0.021 and P=0.011, respectively). Also, multivariate analysis showed that lower ß-catenin expression was independently associated with poorer outcome (P=0.044). CONCLUSION: Human papillomavirus-related tumours show better prognosis and outcome; besides, they do not progress through EMT phenomenon. Immunohistochemical analysis of ß-catenin in invasive tumour front is a key issue for establishing prognosis of vulva cancer.

Clinical Outcomes Among Elderly People With Burns.

Burns in the elderly are a public health concern. This study aimed to analyze etiology, clinical characteristics, and independent risk factors for outcomes of burns in elderly patients. This retrospective study included elderly patients (65 years and over) admitted to a major burn unit between 2006 and 2016. Demographic data, clinical characteristics and outcomes were analyzed. One hundred and thirty patients were included. Most were female (56.2%) and the highest incidence was among those aged 75-84 years. The median burn area was 10.5%. The incidence in winter (50%) was higher (p<0.001) and flame burns predominated (p<0.001). The mortality rate was 32.3%. Independent risk factors for death were older age, larger extent burns, need for escharotomy, and cardiac disease as comorbidity. Amongst the survivors, the median length of stay was 36 days. Development of pressure sores, need for skin grafts, larger extent burns, presence of full-thickness burns, and cardiac disease were shown to be significantly associated with increased length of stay amongst survivors. Preventive measures should target women aged between 75-84 years. Flame burns occurred more frequently in winter. Prognosis is related to age, extent of burns, need for escharotomy at admission, and cardiac disease.

Les brûlures du sujet âgé représentent un problème de santé publique. Cette étude rétrospective se penche sur les étiologies, les caractéristiques et l'évolution de cette pathologie. Elle concerne les 130 personnes de 65 ans et au-delà hospitalisés dans un CTB entre 2006 et 2016. Leur majorité (56,2%) étaient des femmes et la décennie 75-84 ans était la plus représentée. La surface touchée médiane était de 10,5%, les brûlures par flamme prédominaient (p<0,001) et il existait un pic hivernal (50% des brûlures, p<0,001). Les facteurs indépendants de mauvais pronostic étaient l'accroissement de l'âge et celui de la surface brûlée, la nécessité d'incision de décharge et les comorbidités cardiaques. La DMS médiane des survivants était de 36 jours. La survenue d'escarre, la présence de brûlure profonde (et corrélativement la nécessité de greffes), l'augmentation de la surface brûlée et l'existence d'une cardiopathie allongeaient la durée de séjour des survivants. La cible préférentielle des mesures préventive apparaît donc être la population féminine entre 75 et 84 ans. Les brûlures surviennent plus souvent en hiver et sont plus graves quand l'âge et la surface augmente, quand une incision de décharge est nécessaire et chez les "cardiaques".

Association of dental hypersensitivity and anxiety in children with molar-incisor hypomineralisation (MIH).

AIM: The objective of this study was to investigate whether dental hypersensitivity and dental fear were linked to the presence and severity of MIH. METHODS: For this cross-sectional study, 1830 students between the ages of 6 and 12 years were recruited from four randomly selected schools. The Children's Fear Survey Schedule-Dental Subscale questionnaire was used to assess dental anxiety and fear. The children's self-reported dental hypersensitivity resulting from MIH was evaluated using the Wong-Baker Facial Scale and the Visual Analog Scale (VAS). RESULTS: MIH was correlated with tooth hypersensitivity, particularly in severe cases. Dental fear was present in 17.4% of the children with MIH, but it was not associated with dental hypersensitivity, gender, or age. CONCLUSION: No association was found between dental fear and dental hypersensitivity in children with MIH.

Pushing the frontiers of first-principles based computer simulations of chemical and biological systems.

The Laboratory of Computational Chemistry and Biochemistry is active in the development and application of first-principles based simulations of complex chemical and biochemical phenomena. Here, we review some of our recent efforts in extending these methods to larger systems, longer time scales and increased accuracies. Their versatility is illustrated with a diverse range of applications, ranging from the determination of the gas phase structure of the cyclic decapeptide gramicidin S, to the study of G protein coupled receptors, the interaction of transition metal based anti-cancer agents with protein targets, the mechanism of action of DNA repair enzymes, the role of metal ions in neurodegenerative diseases and the computational design of dye-sensitized solar cells. Many of these projects are done in collaboration with experimental groups from the Institute of Chemical Sciences and Engineering (ISIC) at the EPFL.

[Microbiological profile and antibiotic susceptibility patterns of organisms isolated from diabetic foot ulcers in a Portuguese hospital]. / Caracterização do perfil microbiológico e de sensibilidade antimicrobiana dos microorganismos isolados em úlceras diabéticas de doentes de um hospital Português.

OBJECTIVES: To determine the microbiological profile and antibiotic susceptibility patterns of organisms isolated from diabetic foot ulcers in a Portuguese hospital. METHODS: Microbiological data from ambulatory and hospitalized patients with diabetic foot infection during the year 2010 were retrospectively analysed. The profile of the isolated organisms was identified, regarding their prevalence both in the outpatient and inpatient settings. Multidrug-resistant organisms ( MDRO ) under surveillance program at the hospital and their antibiotic susceptibility tests were analysed. RESULTS: Gram-positive aerobes were most frequently isolated ( 59.6 % ) from outpatient diabetic foot ulcers. Staphylococcus was the main genus identified ( 49.8 % ), of which 70.0 % were methicillin-sensitive Staphylococcus aureus. Considering samples obtained from hospitalized patients, Gram-negative aerobes were dominant ( 63.3 % ), mainly Pseudomonas aeruginosa ( 35.5 % ). Staphylococcus aureus represented 22.2 % of all isolates, with 60.0 % methicillin-resistance. Extended spectrum ß-lactamase production and methicillin resistance was noted in 35.0 % and 38.0 % of all bacterial isolates, respectively. High levels of resistance were also documented for Pseudomonas aeruginosa and Acinetobacter baumannii complex. CONCLUSIONS: Epidemiological differences seem to exist between the outpatient and inpatient settings concerning the microbiological profile of clinically infected diabetic foot ulcers. MDRO are prevalent in this study. Other studies are needed in order to adapt empirical therapy to the portuguese reality.

Communication from the cerebellum to the neocortex during sleep spindles.

Surprisingly little is known about neural activity in the sleeping cerebellum. Using long-term wireless recording, we characterised dynamic cerebro-thalamo-cerebellar interactions during natural sleep in monkeys. Similar sleep cycles were evident in both M1 and cerebellum as cyclical fluctuations in firing rates as well as a reciprocal pattern of slow waves and sleep spindles. Directed connectivity from motor cortex to the cerebellum suggested a neocortical origin of slow waves. Surprisingly however, spindles were associated with a directional influence from the cerebellum to motor cortex, conducted via the thalamus. Furthermore, the relative phase of spindle-band oscillations in the neocortex and cerebellum varied systematically with their changing amplitudes. We used linear dynamical systems analysis to show that this behaviour could only be explained by a system of two coupled oscillators. These observations appear inconsistent with a single spindle generator within the thalamo-cortical system, and suggest instead a cerebellar contribution to neocortical sleep spindles. Since spindles are implicated in the off-line consolidation of procedural learning, we speculate that this may involve communication via cerebello-thalamo-neocortical pathways in sleep.

Calvarial graft resorption index in the reconstruction of the maxillary sinus in patients with atrophic maxillas: a prospective clinical study.

The objective of this study was to assess the resorption index of particulate calvarial grafts in maxillary sinuses of patients undergoing total reconstruction of an atrophic maxilla with residual alveolar bone that was less than, or equal to, 3mm thick. Twenty-one maxillary sinus floor elevations were carried out using particulate calvarial grafts in 11 individuals with totally edentulous maxillas. All patients had computed tomography (CT) before (T0), and 48hours (T1) and six months after surgery (T2). For each CT scan, linear measurements were taken of sections of the anterior, medial, and posterior regions of the maxillary sinus. There was a significant increase in the height of the maxillary sinus floor when T0 was compared with T1 (p=0.001). There was a statistically significant reduction in all maxillary sinus measurements when T1 was compared with T2; the mean height reduction being 2.36mm (16.87%) in the anterior region, 3.53mm (22.47%) in the medial region, and 2.21mm (22.78%) in the posterior region (p=0.001). Mean resorption was 20.7%. Autogenous calvarial bone used alone is an option for graft material in pneumatised maxillary sinuses and in cases where there is limited alveolar bone.

[Varicose veins of lower limbs: progress in the surgical management]. / Varizes dos membros inferiores: Progressos no tratamento cirúrgico.

Varicose veins are part of the spectrum of Chronic Venous Disease. They are very prevalent, especially among women and involve mainly the great saphenous vein.Pathogenesis of varicose veins is complex and multifactorial. There is a valvular incompetence as well as a dilation in the vein wall. However, the sequence in which these mechanisms occur is unknown. Probably the valves become incompetent secondary to vein wall abnormalities.The first description of the surgical technique used today came in the transition from the nineteenth to the twentieth century. In the last decade, the great debate evolved around the new techniques of endovascular radiofrequency and laser ablation. These follow the global trend of Medicine to use less invasive techniques.This study, besides performing a contextualization and review of concepts about varicose veins, especially intends to launch the latest data on the state-of-the-art regarding the treatment of this disease, and stands on data collected from Pubmed.It gets clear that endovascular techniques are safe and effective, besides revealing better results in terms of postoperative morbidity when compared with classic surgery. However, the last decade was marked by constant improvements in techniques, creating difficulties in interpreting data presented in trials. Furthermore, there is progressively greater difficulty in randomizing patients, given their preference for less invasive procedures over traditional surgery. New trials on the long-term efficacy in addition to detailed analysis of costs will also be crucial for the implementation of these new methods.

Versatility of the Supraclavicular Flap in Head and Neck Reconstruction.

Objective: Head and neck oncologic resections often leave intricate defects whose reconstruction remains a challenge. The pedicled supraclavicular artery perforator flap is an emerging option, and its applicability in head and neck reconstruction is gaining popularity. Methods: A retrospective analysis of patients regarding medical history, surgical indication, surgical technique, postoperative complications, and outcomes was carried out on all patients admitted to undergo pedicled supraclavicular artery perforator flap reconstruction within our institution. Results: Nine pedicled supraclavicular artery perforator flap reconstructions were performed. Surgical indications were 3 pharyngocutaneous fistulas, 2 tracheoesophageal fistulas, 2 cutaneous defects, 1 immediate pharyngoesophageal reconstruction, and 1 cutaneous and intraoral defect. All flaps survived completely. Excluding one patient who required a second flap due to plate reexposure, the remaining functional and esthetic outcomes were good. Conclusions: The pedicled supraclavicular artery perforator flap is reliable, is quick to harvest, and entails minimal donor site morbidity. Also, it is thin, is pliable, and has a wide arc of rotation, making it extremely versatile. It is an option that should be added to the spectrum of solutions of any head and neck reconstructive surgeon.

Routine post-weaning handling of rats prevents isolation rearing-induced deficit in prepulse inhibition.

Rats reared under isolation conditions from weaning present a number of behavioral changes compared to animals reared under social conditions (group housing). These changes include deficits in prepulse inhibition (PPI) of the startle reflex to a loud sound. PPI refers to the reduction of the magnitude of the startle reflex when a relatively weak stimulus (the prepulse) precedes by an appropriate time interval the intense startle-elicing stimulus (the pulse). PPI is useful for studying sensorimotor integration. The present study evaluated the effect of handling on the impairment of PPI induced by isolation-rearing. Male Wistar rats (N = 11-15/group) were housed in groups (5 per cage and handled three times a week) or isolated (housed individually) since weaning (21 days) for 10 weeks when they reach approximately 150 g. The isolated rats were divided into "minimally handled" animals (handled once a week for cleaning purposes only) or "handled" animals (handled three times a week). This handling consisted of grasping the rat by the tail and moving it to a clean cage (approximately 5 s). A statistically significant reduction (52%) in the PPI test was found only in the isolated group with minimal handling while no difference was seen between grouped animals and isolated handled animals. These results indicate that isolation rearing causes disruption in the PPI at adult age, which serves as an index of attention deficit. This change in the sensory processing of information induced by post-weaning isolation can be prevented by handling during the development of the animal.

Effects of a Lasiodora spider venom on Ca2+ and Na+ channels.

The venom of a Brazilian spider, Lasiodora sp (Mygalomorphae, Theraphosidae), was screened for activity against ion channels using Ca2+ imaging and whole-cell patch clamp in GH3 cells. When tetrodotoxin (TTX) was present to block Na+ channels, the venom abolished the Ca2+ oscillations that are normally present in these cells and reduced the basal level of intracellular Ca2+. Under patch clamp, the venom reduced the L-type Ca2+ channel conductance and caused a positive shift in its voltage dependence of activation. In addition to these effects, when applied without TTX, the venom also caused a slow and noisy increase in intracellular Ca2+. The sensitivity of this second effect to TTX suggested an effect on Na+ channels, which was tested using patch clamp. Control Na+ currents inactivated completely as a single exponential. Treatment with the venom did not affect the amplitude of I(Na), but caused it to divide in two slower exponential components plus a sustained component, all of which were suppressed by TTX. The venom also caused a negative shift in the voltage dependence of activation and steady-state inactivation of I(Na). The observed effects of this venom on whole-cell currents explain the changes it causes in intracellular Ca2+ in GH3 cells and demonstrate that the venom of this spider is a source of toxins active against ion channels.

Balloon tamponade of the pharynx in transnasophenoidal operations: technical note.

The authors present a new technique for tamponade of the nasopharynx after the performance of a transnasophenoidal approach to the hypophysis. This technique consists of placing a Foley balloon catheter in each nasal cavity, extending to the nasopharynx. The position of the balloons and the adequacy of the amount of radiopaque substance used to fill them is determined with x-ray films or a television image intensifier. Among the advantages of the method over tamponade with Vaseline-covered gauze are: (a) better tamponade; (b) the possibility of testing the position and volume of tamponade; (c) the absence of trauma to the nasopharyngeal mucosa upon removal of the catheters after deflation of the balloons; (d) the availability of two airways for respiration in addition to the mouth; and (e) the absence of blood gas alterations and infections.

Do steroids interfere in dyspnoea sensation?

Dyspnoea remains a remarkable clinical problem and a therapeutic challenge, mainly in chronic respiratory conditions. This study investigated the potential effects of steroids on dyspnoea sensation regardless of their pulmonary anti-inflammatory actions. Sixteen healthy men (mean age +/- SD = 22.5 +/- 1.6 years) developed uncomfortable breathing by the use of inspiratory resistors (loads of 0, 7, 14 and 21 cm H2O/l/s) and breathholding 6 h after taking 40 mg of prednisone (Pred) or placebo (Plac). Respiratory discomfort during breathing with loads was evaluated with a 100 mm visual analog scale. The maximum voluntary apnoea time did not differ between the prednisone and placebo days (Plac = 96 +/- 11.8 s x Pred = 105 +/- 12.2 s) and prednisone did not influence the dyspnoea sensation induced by different inspiratory loads (0 cm H2O/l/s: Pred = 2.8 mm x Plac = 1.9 mm; 7 cm H2O/l/s: Pred = 18.3 mm x Plac = 18.6 mm; 14 cm H2O/l/s; Pred = 33.0 mm x Plac = 34.1 mm; 21 cm H2O/l/s: Pred = 48.1 mm x Plac = 49.6 mm). Prednisone intake was associated with a significant increase in minute ventilation during breathing with no inspiratory loads (Pred = 11.91 +/- 1.28 l/min- x Plac = 9.95 +/- 0.86 l/min). Although steroids certainly may improve respiratory conditions due to anti-inflammatory actions, available evidence does not support any specific beneficial effect of these drugs on these perception of dyspnoea itself.